Joule Thief

[Pirate88179]

Jeanna:

I have to agree that winding the toroids where you can actually pass the spool through is important to me.  OK, so I am lazy, I admit it.  Heck, I barely had the patience to wind those 330 or so winds when I could pass the spool through, ha ha.

Great job on locating the distributor for the source of these toroids.  I am sure this will be very helpful here to a lot of folks.

Thank you for taking the time to evaluate all of this.  You are a true experimenter and researcher Jeanna.  I am so glad you are here.

Bill

[jeanna]

And are you saying that they are as good as out big cores ?
.... . I can carry some on the site if need be . I would like 30 bucks worth at least .Also do they have BIg one also?

These came as free samples from the MMI company as did yours and Bills.
I am hoping people will be getting these from you.
My first desire was to prove that the big one with the W core is the one we want.

We had 2 experts here who disagreed and I wanted proof.
And, yes, the W which is very high permeability is better.
I will be winding a toroid tonight and tomorrow using the 2 smaller ones. See, the J of the smaller is as good as the W of the bigger one.
I wanted to test these.
Yes we can all get 30 dollars worth of the 1 kind, but what if the 2 1/2 is as good? Or better?
I had also asked for a 1 1/2 inch one which might be as good, but it was not in the sample department.

I do not know the stock of the company in CA. I will ask them tomorrow.

Remember that recently I have made a 411 volt secondary from the little tor-23 which is available and 10 cents each.
That high voltage was not even necessary to make that bright globe lamp. (=brighter than the cfl with the biggo toroid)

According to the formula given on the gsu website the cross sectional area (A)  of the toroid material is an important element. The fatter the donut the more food. Also the smaller the overall diameter the better.(/ 2pi r) I wanted to check this out with materials whose permeability is known.

It works too.
The 2 1/2 inch toroid is both narrower in OD and chunkier in material and it has a much higher inductance ( L) value.

We have waited this long, so I want to follow up with the company so they understand what is going on. You can place an order before I make my next light if you want to. It will only cost you extra shipping and bigger stock if it turns out to be something lots of people want. So, I say wait.

It is up to you.

xee2 just posted the numbers of what I have as samples.

jeanna

[jeanna]

@ jeanna

Using your inductance data, the relative permeability for the W material is 15,000.

Inductance in mH of a single coil on the 3.38" toroid is =  0.0777 x (number of turns squared)

(adding more coils on same toroid will change inductance of any coils already on toroid)

Thanks for taking the data.

You are welcome.
In fact the measured  inductance of  3 turns is what is .077mH not one turn.

I think we can count on these being good toroids.

@Bill.
I understand about not liking to spool off and cut before winding, but remember that you needed to gouge out the box a little to fit that toroid.
It will be a personal preferences thing in the end, but I think there are others like me who like little and light.

I'm gonna wind one and see.

jeanna

[Pirate88179]

Jeanna:

Well, it is extra hard when you live with a cat.  She was attacking the wire when it was on the spool.  Can you imagine what she would do if it were lying in a mass on the floor?  She is 16+ but still a highly trained attack cat.

Bill

[jeanna]

Jeanna:

Well, it is extra hard when you live with a cat.
.... highly trained attack cat.

Bill

That is funny, Bill.

I will wind a real one tomorrow.
I just made one with 2T,6T,26T and the 26 turns took one wingspan or around 5 feet.
(This is enough for 84T on the tor-23 which lights a neon.)
This gets close but 164v is not enough to light a neon when they are pointy spikes.
The frequency here is 26khz and very promising.
I will wind 13 times that for a 330 turn secondary and see how it goes.
Maybe a straw will make a good winding bobbin.

I too do not love having the wire all around me, even without a cat.
I am happy to report that the
OW48613TC is the one we want lots of.
If you or gadget or anybody wants to order a bunch of them tomorrow, I say go for it.


jeanna